...a snake has 1) bacterial gastroenteritis (gut infection); 2) no active infection but is or has been recently stressed; 3) bile mal-reabsorption (bile is secreted but no food is eaten so bile passes through and stains urates/stools; 3) systemic infection, with bacterial/immune "complexes" excreted in urine...
...first thing to do is check/set-up proper conditions: hot spot 95F... cool end:day 84-86, night 82-84...humidity around 60%...hide spot at warm end...fresh water in easily accessible/spill-proof bowl...CLEAN paper substrate that is easy to change (I use paper towels or unprinted newsprint)...
...then, after a few days offer a SMALL meal, do not try to set any records here...a small meal is critical...whatever it prefers, live,f/k,f/t, whatever...make it small...if it eats, great...wait 3-5 days and do it again, same small meal...if it doesn't eat, THEN it's time to seek vet attention...
Good luck!
Scott J. Michaels DVM
Serpent City
PS pic...BP's, like other pythons, often will lay on their backs to get comfortable...this is not an indication of IBD or anything pathologic, but it's sure alarming the first few times you see it!
